JP2013515420A - Control of service quality in relays - Google Patents

Abstract

The present invention provides a method in a communication system, wherein a plurality of user equipments transmit data to a donor node via a relay node, and the plurality of user equipments are transmitted before transmission to the relay node. Each stores data in its own UE buffer, and the relay node stores data received from multiple user equipments in the relay buffer prior to transmission to the donor node. The method sends a relay buffer status report from the relay node to the donor node when the buffered data value exceeds a threshold at the relay node. The buffered data value represents either data stored in the UE buffer or data stored in the relay buffer.

Description

  The present invention relates to a mobile communication system, and more particularly, to a method for transmitting and receiving data using a relay. A relay provides the same functionality as a conventional base station, but provides a link to the network, for example by using the same radio interface used by a mobile device that connects to the relay.

  The present invention is in accordance with OFDMA systems such as those used in WiMAX, UMTS (Universal Mobile Telecommunication System), CDMA (Code Division Multiple Access) protocol, GERAN (GSM® EDGE Radio Access Network) or other telecommunications protocols. It may be used in a working communication system. In particular, the present invention may be used in a telecommunications protocol where a relay station is used between a user equipment and a base station for data transmission.

  One particular application is UMTS, also known as 3G. UMTS wireless communication systems are being developed on a global scale. Future development of the UMTS system is concentrated on the so-called evolved UMTS Terrestrial Radio Access Network (ETRAN), commonly referred to as the project name LTE (Long Term Evolution).

  LTE is a technology for the transmission of high-speed data services with increased data rates for users. Compared to UMTS or previous generation mobile communication standards, LTE also provides reduced delay, increased cell edge coverage, reduced cost per bit, flexible spectrum usage, and multi-radio User equipment with multi-radio access LTE designed and providing a peak data rate in the downlink (DL) direction communication from the base station (BS) to the user equipment over 100 Mbps, while over 50 Mbps The peak data rate is given in the uplink (UL) direction communication from the BS to the BS.

  LTE-A (LTE-Advanced), a development that is currently standardized, further improves LTE systems that allow up to 1 Gbps in the downlink and 500 Mbps in the uplink. LTE-A uses new techniques to improve performance through existing LTE systems, especially for high data rate transmission and improved cell edge coverage.

  LTE-A and LTE share a common basic architecture and network protocol. As in current UMTS systems, the basic architecture proposed for LTE consists of a radio access network (eUTRAN) that connects users (more precisely, user equipment) to access nodes that function as base stations, and these The access node is linked to the core network. In eUTRAN terminology, an access node is called an extended node base station or eNB (enhanced Node Base-station). A separate radio network controller (RNC) used in the previously proposed system is no longer required, some of its functionality is built into the eNB and some are mobility management entities (MMEs). Some are built into SAE GW (System Architecture Evolution Gateways). The eNB connects to an evolved packet core (EPC) and a core network called in LTE.

  FIG. 1 shows the relationship between LTE protocol layers. PDCP (Packet Data Converge Protocol) is an upper sublayer of LTE layer 2 (a layer of a protocol stack between the IP layer and the physical layer) above an RLC (Radio Link Control) layer. The PDCP layer processes control plane messages such as RRC (Radio Resource Control) messages in the control plane, and processes user plane packets such as IP (Internet Protocol) packets in the user plane. Depending on the radio bearer, the main functions of the PDCP layer are header compression, security (integrity protection and encryption), reordering and re-transmission during handover. (Retransmission) is supported. The PDCP packet includes a sequence number (SN) that allows for the identification of the missing packet by in-order delivery of the packet to higher layers and the potential retransmission of the missing packet. The sequence number is used for security in the encryption of the user plane and the control plane, and further for protecting the integrity of RRC data in the control plane. An equivalent protocol structure exists in the UMTS protocol.

  FIG. 2 shows a network topology between the user equipment 110, the two extended node base stations 120 and 121, and the service gateway 130 (SGW or S-GW). The Uu radio interface corresponding to the broken line marked “Uu” in FIG. 1 is marked, and similarly, S1-U marked in FIG. 2 is the broken line marked “S1-U” in FIG. Corresponding to The user equipment 110 and the eNB 120 communicate through the Uu radio interface. The two eNBs 120 and 121 communicate with each other via a wired X2 interface.

  LTE-Advanced extends LTE Rel-8 by providing support for relaying as a tool to improve data throughput to user equipment at the cell edge. Relaying also improves group mobility and temporary network deployment and provides coverage in new areas. LTE-Advanced is used as an example, but relaying is supported in other communication protocols, for example, a similar relaying technology exists in IEEE standard 802.16j.

  FIG. 3 shows a network topology in a configuration in which the user equipment 110 communicates with the donor extended node base station (DeNB) 120 via the relay node 140. The user equipment 110 communicates with the relay node 140 through the Uu radio interface. The relay node 140 communicates with the DeNB 120 through the Un radio interface. The DeNB 120 and the eNB 121 communicate via the X2 interface. DeNB120 and eNB121 each communicate with sGW130 via a S1-U interface.

  Through two radio interfaces (Uu and Un), user data traffic consists of user planes (PDCP (Packet Data Converge Protocol), RLC (Radio Link Control), MAC (Medium Access Control) and PHY (PHYsical) protocol layers. Transmitted).

  The relay node 140 is wirelessly connected to the radio access network via the donor node 120 serving the donor cell. LTE-A specifically provides support for relay nodes through in-band connections. In an in-band connection, the network-relay link shares the same frequency band as the direct network-UE link in the donor cell served by the donor node. Other telecommunication protocols also support “out-band” connections, where the network-relay link is the same as the direct network-UE link in the donor cell served by the donor node. Does not work in the band. In particular, LTE-A supports “type 1” relay nodes. Type 1 relay nodes are characterized by the following, as described in TR 36.912 (Feasibility Study for Further Enhancements for E-UTRA (LTE-Advanced)).

A Type 1 relay node controls one or more cells, and each of the one or more cells appears to the user equipment as a separate cell different from the donor cell.
One or more cells have their own physical cell ID (defined in LTE Re-8) and transmit their own synchronization channel, reference symbols and other parameters.
In an environment of single cell operation, the user equipment receives scheduling information and HARQ feedback directly from the relay node, and sends its control channel (SR / CQ / ACK) to the relay node.

  As used herein, the term “bearer” means a stream of data between two points defined by a set of parameters. A bearer encompasses a “radio bearer” which means a radio stream between two points defined by a set of parameters. Bearers are distinguished from each other by their endpoints and by labels that represent their defining parameters, such as QoS labels. A bearer includes more than one data stream, for example when the data streams have a common QoS label.

Typically, multiple applications may be run simultaneously on the user equipment, each application requiring data to be sent to the donor node via the relay node, and from the donor node via the relay node. Requires data to be received. For example, a user is engaged in VoIP (Voice over IP) and at the same time browsing a web page or FTP (File Transfer Protocol) application (a confirmation message is sent from the user device to the donor node). Download the file using VoIP has more stringent quality of service (QOS) requirements than web browsing and FTP in terms of delay and delay jitter, while the latter requires a very low packet loss rate. In order to support multiple QoS requirements, different bearers are set up for user equipment in the network architecture, and each bearer is associated with a particular QoS cell. In general, bearers are divided into two categories based on the nature of QoS.
A minimum GBR (Minimum GBR) bearer is used for applications such as VoIP. These are permanently assigned dedicated transmission resources during the bearer establishment / change procedure (eg by admission control function in eNodeB). A higher bit rate than GBR is allowed for GBR bearers when resources are available. In such a case, the MBR (Maximum Bit Rate) parameter is associated with the GBR bearer and sets an upper limit on the bit rate expected from the GBR bearer.
Non-GBR bearers do not guarantee a specific bit rate. These bearers are used for applications such as web browsing or FTP transfer. For these bearers, bandwidth resources are not permanently allocated to the bearers. In the access network, it is the role of eNobeB to guarantee the QoS required for the bearer through the radio interface. Each bearer has an associated QCI (QoS Class Identifier) and ARP (Allocation and Retention Priority). Each QCI is characterized by priority, packet delay quota and acceptable packet loss rate. The bearer QCI label determines how the eNodeB is processed. A set of standardized QCI and other properties (which can be selected by the Policy Charging Rule Function (PCRF in EPS)) is described in section 6.1.7 in (3GPP Technical Specification 23.203, Policy and charging control architecture (Release 8). Provided in Table 1). The QCI table specifies a priority processing value, an allowable delay allocation amount, and a packet error loss rate for each QCI label (QoS classification identifier).

  The priority from the QCI label and the packet delay quota (and to some extent, acceptable packet loss rate) determine the RLC mode configuration (eg, schedule policy, queue management policy and rate shaping policy perspective) The scheduler at the MAC decides how to process packets sent through the bearer. The RLC mode has no RLC overhead, for example, a transparent mode used for broadcast SI messages, a confirmation mode (AM) in which a network component receiving a data packet confirms reception, and reception of a data packet is confirmed. One of the unconfirmed modes (UM).

  For example, packets with high priority are expected to be scheduled before packets with low priority. For bearers with low acceptable loss rates, acknowledgment mode (AM) is used within the RLC protocol layer to ensure that packets are successfully transmitted across the air interface. The bearer ARP is used for call admission control, i.e. to determine whether the requested bearer should be established in case of radio congestion. Also, the ARP bearer dominates the bearer priority for preemption with respect to the request for establishment of a new bearer. Once successfully established, bearer ARP does not affect bearer level packet forwarding processing (eg, for scheduling and rate control). Such packet transfer processing is determined only by other bearer level QoS parameters such as QCI, GBR and MBR.

  FIG. 4 illustrates the use of bearers in a conventional LTE / SAE (System Architecture Evolution) system. In this example, there is no relay node. Interfaces between different network components or nodes are indicated by broken lines. The Evolved Packet System (EPS) bearer has a plurality of interfaces, that is, an S5 / S8 interface from P-GW (Packet GateWay) to S-GW, an S1 interface from S-GW to eNodeB, and an (Uu interface from eNodeB to UE). (Also known as) need to traverse the radio interface. Over each interface, EPS bearers are mapped to lower layer bearers where they have their own bearer identity. Each node keeps track of the binding between bearer IDs across its different interfaces. For example, the S5 / S8 bearer transmits an EPS bearer packet between the P-GW and the S-GW. The S-GW stores a one-to-one mapping between S1 bearers and S5 / S8 bearers. The bearer is identified by a GTP tunnel ID across both interfaces.

  End-to-end services are provided by EPS bearers connected to external bearers by P-GW. The EPS bearer is provided by an S5 / S8 bearer connected to an E-RAB (E-UTRAN Radio Access Bearer) by the S-GW. E-RAB is provided by the S1 bearer connected to the radio bearer by the eNodeB. The LTE architecture is used in this example to illustrate the bearer concept, but it should be understood that similar architectures exist in other communication standards or protocols.

  FIG. 5 illustrates as an example the messaging required to set up a bearer using a conventional LTE / SAE bearer establishment process. In this example, there is no relay node. The MME constructs a set of session management phone configuration information including UL TFT (Traffic Flow Template) and EPS bearer identity, includes the constructed set in the Bearer Setup request message, and the MME includes this message. The message is sent to the eNodeB (message 4 in FIG. 5). The session management configuration is NAS (Non-Access Stratum) information and is therefore transmitted transparently from the eNodeB to the UE. The bearer setup request also provides the bearer QoS requirements to the eNodeB, and this information is used by the eNodeB for connection admission control and to ensure the required QoS by appropriate scheduling of the user's IP packets. The The eNodeB maps the QoS of the EPS bearer to the QoS of the radio bearer. The eNodeB then communicates an RRC connection reconfiguration message (including the radio bearer QoS, session management configuration and EPS radio bearer identity) to the UE to set up the radio bearer. The RRC connection reconfiguration message includes all configuration parameters for the radio interface. This is mainly for the Layer 2 configuration (PDCP, RLC and MAC parameters), but the same is true for the Layer 1 parameters required for the UE to initialize the protocol stack.

  In this specification, bearer processing in a communication system in which a user equipment communicates with a base station via a relay or relay node is considered. In particular, this specification addresses how the rapidly changing QoS requirements of user equipment connected to a relay can be accommodated in the QoS requirements of the interface between the relay and the base station. .

R2-094634 (3GPP TSG-RAN WG2 # 67,24th-29 th AUG 2009, Shenzhen, China, Discussion on alternative on Relay, LG Electronics) is to form part of the discussion in the establishment of the LTE-A standard And describes the use of bearer GBR and MBR parameters. R2-094634 discloses that for a given UE, the QoS parameters may be semi-static during the call. However, for an RN that continuously manages incoming and outgoing UEs, the QoS parameters of the operating Unbearer (between the RN and the eNodeB) are not semi-static. When a new UE under RN control initiates or terminates a call, GBR and MBR parameters are updated between DeNB and EPC as well as between RN and DeNB.

  R2-094634 is provided for VoIP services as provided in (LTE) Rel-8. Due to further hops, the delay across the radio interface is more important for VoIP over RN. Thus, whenever the number of VoIP calls handled by the RN changes, this change should be immediately reflected in parameter changes through the Un interface.

  R2-094619 (3GPP TSG RAN WG2 # 67, 24-28 August 2009, Shenzhen, China, Consideration on MAC procedures for Uninterface, ETRI) provides information on the amount of data in the uplink buffer of the UE. It is proposed that the procedure of Buffer Status Report) be performed. The normal Media Access Control (MAC) procedure at the Un interface allows relays to provide their buffer state to the DeNB for uplink backhauling. However, this procedure is triggered only after the UE UL data has reached the relay's uplink buffer and the relay reports the buffer status by calculating the size of the buffered data. In order to minimize the relay delay of uplink data transmission resulting from reporting, R2-094619 proposes that the relay initiates the BSR procedure sooner than allowed according to the current MAC specification.

  R2-094619 proposes to trigger the BSR procedure immediately after the relay receives the BSR from the UE. In addition, the relay transmits a BSR including not only information regarding buffered data but also BSR information received from the UE. The UE data associated with the BSR arrives at the relay's uplink buffer when the relay receives an uplink grant from the DeNB. Since the BSR indicates the amount of UE data available for transmission, the relay guarantees the processing of the transmission unless an exceptional error occurs. Therefore, the relay transmits the uplink data of the UE in cooperation with the DeNB scheduling.

  According to an embodiment of the first aspect of the present invention, there is provided a method in a communication system, wherein a plurality of user equipments transmit data to an uplink to a donor node via a relay node; Each of the plurality of user equipment stores data in its own UE buffer before transmission to the relay node, and the relay node is received from the plurality of user equipment in the relay buffer before transmission to the donor node. Remember the data. The method sends a relay buffer status report from the relay node to the donor node when the buffered data value exceeds a threshold at the relay node. The buffered data value represents either the data stored in the UE buffer or the data stored in the relay buffer.

  Advantageously, signaling overhead can be saved by sending a relay buffer status report to the donor node once the threshold is exceeded. The threshold is set so that the buffered data value is at a point where it is necessary or confronted to change the transmission characteristics or radio resources allocated to transmit data from the relay node to the donor node. The

  The communication system is a wired or wireless communication system, but in further embodiments, some features may be limited to use in a wireless communication system. In particular, the communication system is suitable for operating according to the LTE-Advanced communication protocol. In the case of the LTE-Advanced protocol, the donor node is an eNB access node. As a further alternative, the communication system may operate in a hybrid network including LTE eNBS and LTE-A eNB.

  In a preferred embodiment, there is a radio interface between the relay node and the donor node, between each of the plurality of user equipments and the relay node, and data transmission between these components is by radio waves.

  The user equipment is a mobile terminal such as a telephone or PDA, but is not limited to such equipment. For example, a desktop type personal computer may join the communication system as a user device.

  The relay node shares the same frequency band as the direct link from the donor node to the user equipment in the donor cell served by the donor node. In this way, the donor node effectively provides some bandwidth for use by the relay node. From the user equipment perspective, a relay node provides the same or similar functionality as a base station or other access node, but the link to the network is the same radio interface used by the user equipment connecting to that relay Provided by using. A donor node is a base station which communicates with a user apparatus via a relay or relay node.

  Each user equipment has at least one UE data to store data before transmission to the donor node. The user apparatus sends two different types of data to the relay node, for example, VoIP (Voice over IP) data and a packet confirmation response of the downloaded electronic mail.

  Depending on the particular embodiment, the buffered data value represents either the amount of data stored in the UE's data buffer or the amount of data stored in the relay data buffer. In either case, a comparison with the threshold is performed by the relay node. Optionally, the relay node may provide a buffered data amount value representing the amount of data stored in the UE data buffer based on the UE buffer status report sent from the plurality of user equipments to the relay node. Hold. The user equipment sends a UE buffer status report to the relay node in response to a specific event trigger, for example, the amount of data stored in one of the UE data buffers at a particular user equipment Since a certain amount of time is required to transmit to the relay node, a specific UE sends out a UE buffer status report. Alternatively, UE buffer status reports may be sent periodically to provide a relay node with an indication of the amount of data in each of the UE's data buffers at a particular user equipment. The period between such periodic UE buffer status reports may be fixed or dynamic according to the environment in the communication system.

  Alternatively, buffered data values do not represent the amount of data, but increase or decrease in the amount of data buffered over a given length of time, or of buffered data such as generations. It may represent other characteristics.

  The buffer status report includes information regarding the amount of buffered data in the relay buffer, UE buffer, or a combination of both.

  Preferably, the user equipment sends a UE buffer status report to the relay node both periodically and upon the occurrence of a trigger event. Furthermore, the UE buffer status report preferably includes an indication of the amount of data in each UE's data buffer, which is preferably done in conjunction with identifying the specific UE's data buffer. . For example, the method of identifying this buffer is a DRB (data radio bearer) ID or possibly a logical channel ID through the Uu interface for a certain UE application session.

  Optionally, the lower threshold is exceeded when the buffered data value falls below a certain lower threshold, and the upper threshold is exceeded when the buffered data value exceeds the upper threshold. There are an upper threshold value and a lower threshold value. Alternatively, the threshold defines the rate of change (scalar or direction) of buffered data values that cannot be exceeded. The rate of change is related to time or the number of user equipments in the communication system.

  Preferably, the buffered data value represents a combination of data stored in the UE buffer and data stored in the relay buffer. These data volume combinations (or scaled / normalized representations thereof) provide an accurate indication of the volume of incoming data to be transmitted from the relay node to the donor node, and the combined value exceeds the threshold Only occasionally, sending a buffer status report message to the donor node is a more effective advertising procedure.

  Combining the two values is to add the total amount of data in the UE's buffer and the amount of data in the relay buffer. Alternatively, the values are combined as a scaled representation of the amount of data. The relay node may rely on reports from multiple user equipments for information regarding the amount of data in the UE's buffer, so the relay node has the exact same value for the amount of data in the UE's buffer. There may not be. However, in this specification, the value held by the relay node as the amount of data in the UE buffer is considered to be the amount of data in the UE buffer.

  Optionally, there is a separate threshold for the amount of data in the UE buffer and for the amount of data in the relay buffer so that a buffer status report is sent when either or both of the data amounts exceed the threshold There is a case.

  Optionally, the relay node generates a report that includes a buffered data value that is either the amount of data in the UE buffer, the amount of data in the relay buffer, or a combination of the two, and only once the threshold is exceeded. Send a report to the donor node. The value included in the report is updated periodically or according to other triggers when the associated buffer report is received from the user equipment.

  Preferably, the method includes receiving a relay buffer status report at the donor node, and defining a relay-to-donor node transmission of data based on the received relay buffer status report. Further comprising adjusting the donor transmission characteristics.

  Advantageously, the reporting scheme proposed by the present invention is that a buffer status report is sent from the relay node to the donor node only when a threshold is exceeded, and thus a change in transmission characteristics is required. It is efficient in terms of using signaling overhead. For example, the amount of a given type of data buffered for transmission at the user equipment and / or relay may be large, thus requiring adjustments in extra radio resources and transmission characteristics. Alternatively, the amount of buffered data may be small, in which case the allocated radio resources are reduced and the transmission parameters are adjusted accordingly.

  The donor node may adjust the relay-donor transmission characteristics based on the contents of the buffer status report. The content may indicate the amount of data in the UE buffer, the amount of data in the relay buffer, or both. The adjusted transmission characteristic is, for example, the bandwidth dedicated to transmission from the donor node to the relay node, or the guaranteed bit rate between the two nodes is adjusted and the change in allocated radio resources Leads to.

  In a preferred embodiment, data transmitted from each of the plurality of user equipments to the relay node is a data stream established with a set of UE transmission characteristics for the data stream, including quality of service requirements. Sent. In this case, the method includes defining a set of UE transmission characteristics for each new data stream, and transmitting information representing the defined set of UE transmission characteristics from the relay node to the donor node.

  Data streams are distinguished from each other by their endpoints or by other characteristics that define the data stream, such as quality of service requirements. The data in the data stream is a series of consecutively marked packets. A data packet transmitted in a stream contains some labels or indications of characteristics that define the stream. Once established, the data stream remains established until the end of the associated data transfer session, eg, the end of a VoIP call or the end of a file transfer over FTP.

  The transmission characteristics of the UE include one or more quality of service requirements. Quality of service requirements include minimum delay time, eg endpoint to endpoint, priority level, acceptable packet loss rate, guaranteed bit rate, maximum bit rate, minimum delay variation or minimum average delay It is.

  The information representative of the established UE characteristics may be the entire set of established UE characteristics or a reduced version that includes a summary or label. For example, a predefined set of characteristics known by both the relay node and the donor node are labeled in a predetermined manner. Alternatively, depending on the particular embodiment, the donor node may only need certain information such as GBR and MBR.

  Alternatively, the relay node associates a predetermined label contained in the data stream with a known transmission characteristic or set of transmission characteristics and transmits the relevant information accordingly to the donor node.

  While a data stream is considered to traverse several interfaces, the data stream is transmitted through a particular interface, for example via a bearer that is a radio bearer, and then the data stream, along with other similar data streams, Grouped with another bearer for transmission over the interface. A radio bearer has the same quality of service requirements as one or more data streams. One radio bearer is used per data stream, or several data streams with the same quality of service requirements are grouped or multiplexed on the same radio bearer, for example between a relay node and a donor node May be. These data streams reach relay nodes in their individual radio bearers from their respective user equipment.

  In particular, embodiments of the present invention select, for each set of UE transmission characteristics, a QoS label from a set of QoS labels according to the quality of service requirements of a new data stream at a relay node, and It further includes transmitting a QoS label as information representing the defined set from the relay node to the donor node.

  Advantageously, this provides an efficient way to signal the configuration of the currently active data stream to the donor node in the communication system. Of course, the donor node is made aware and active accordingly when the user equipment leaves the communication system or when the data stream ends, for example at the end of a call or after downloading a file via FTP. The overall view of the data stream can be adjusted.

  A statistic or set of statistic values representing the active data stream and transmission characteristics at the donor node allows the donor node to allocate resources and change the transmission characteristics according to the number and type of data streams between the relay node and the user equipment Make it possible.

  Data streams may be transmitted via radio bearers from relay nodes to donor nodes according to the QoS labels used to summarize the specific quality of service requirements of those data streams. A data stream with similar quality of service requirements is then transmitted from node to node via a radio bearer with transmission characteristics appropriate to the QoS requirements of the data stream.

  Preferably, the method embodying the invention provides the threshold at the donor node based on the QoS label of the currently established data stream for use as a threshold at the relay node, and transmits the threshold to the relay node. Including that.

  The threshold at the relay node is any of the different types of thresholds described above. For example, it can be an upper or lower threshold, or a threshold for the rate of change. The threshold may be compared to any type of buffered data value, for example a percentage or amount, or to a buffered data value representing one or both of the UE buffer and the relay buffer. Is intended.

  The currently established data stream is the data stream that is established and transmitting data, or the transmission characteristics are still established and there are some interruptions in data transmission. The data stream is established at the end of the session in which the data stream was established, for example at the end of a VoIP call or when the file transfer over FTP is finished. The donor node is made aware when the data stream has been established so that an accurate overall image of the currently established data stream is maintained.

  A threshold is preferably provided each time a change in the number of data streams for which the donor node is currently established is notified. For example, if the number of data streams increases, the upper threshold for the amount of data in the UE buffer that needs to be exceeded for buffer status reporting to be sent to the donor node is increased.

  In a preferred embodiment, each user equipment has a UE buffer dedicated to each data stream from that user equipment to the relay node, and the relay node has each of the currently established data streams. Has buffers for different QoS labels.

  Each user equipment may have more than one established data stream in which data is transmitted to the relay node. For example, a user may participate in a VoIP call and have a voice data stream, download an email from a server, and have a packet confirmation data stream. As a further example, the user is streaming video at the same time that he / she makes / receives a voice call, or uses other conventional applications of the default IP network (eg, internet surfing) or makes a voice call / You may be watching mobile TV at the same time to receive. Thus, the user equipment may have a UE buffer for each data stream. If these data streams have different quality of service requirements, different radio bearers may be used for each and thus different buffers. Each user buffer has associated transmission characteristics, which are an established set of transmission characteristics of the data stream from which data from the buffer is sent. Thus, QoS labels or other classifications may be applied to these transmission characteristics, and therefore each user buffer is considered to have a QoS label.

  The preferred embodiment further includes, for each buffer at the relay node, providing a threshold based on the QoS label of the currently established data stream at the donor node and transmitting the threshold to the relay node. In this case, when the buffered data value specific to the QoS label exceeds the threshold provided for the relay buffer with the same QoS label, a buffer status report is sent from the relay node to the donor node and the QoS label The unique buffered data value is the data stored in the UE data buffer dedicated to the data stream with a specific QoS label, the data stored in the relay buffer with the same QoS label, or both Represents a combination.

  Advantageously, providing a threshold dedicated to each relay buffer means that a different threshold is provided for each QoS label. For example, as described above, more than one threshold may be provided for each QoS label, such as there are upper and lower thresholds. By providing one or more thresholds for each QoS label, the donor node can take into account the specific requirements or characteristics represented by each of the QoS labels when setting the threshold. For example, if a data stream is grouped into a radio bearer according to a QoS label for transmission of a relay node to a donor node, a given radio bearer when the value representing the buffer supplied to that radio bearer exceeds a threshold It is preferable to adjust the bandwidth dedicated to the network. A given QoS label requires frequent adjustment of the bandwidth between the relay node and the donor node, in which case only a small increase or decrease from the typical level of data in the buffer is detected. The threshold is set so that the threshold is exceeded.

  A buffered data value specific to a QoS label may represent the amount of data or, for example, a percentage. The relationship between the buffered data value specific to the QoS label and the associated threshold is described above with the buffered data value so that any option or alternative described above is also applicable. It should be considered the same term as the relationship between the threshold values. As described above, the donor node is informed of the transmission characteristics, or the QoS label of the data stream when the data stream is established, and thus the number of currently established data streams with the respective QoS label. Recognize Each time this information changes, the donor node redefines some or all of the thresholds and sends these new values to the relay node.

  According to an embodiment of another aspect of the present invention, there is provided a communication system comprising a plurality of user equipments each having a UE buffer, a relay node having a relay buffer and a donor node. Each user equipment transmits data to the donor node via the relay node in the uplink and stores the data in its own UE buffer before transmission to the relay node. The relay node stores data received from multiple user equipments in the relay buffer before transmission to the donor node and sends a buffer status report to the donor node when the buffered data value exceeds a threshold To do. The buffered data value represents either data in the buffer at the UE or data in the relay buffer.

  According to an embodiment of another aspect of the invention, a relay node is provided for use in a communication system, the communication system also comprising a plurality of user equipment each having a UE buffer, Data is stored prior to transmission on the uplink to the node and donor node. The relay node has a relay buffer, receives data from each of a plurality of user equipment for transmission to the donor node, stores data in the relay buffer before transmission to the donor node, and buffered data When the value exceeds the threshold, a buffer status report is sent to the donor node. The buffered data value represents either data in the UE buffer or data in the relay buffer.

  According to an embodiment of another aspect of the present invention, a donor node is provided for use in a communication system, the communication system each having a UE buffer for storing data prior to transmission of the uplink to the relay node. A plurality of user equipment and a relay node having a relay buffer for storing data before transmission to the donor node. The donor node provides a threshold that triggers the relay node to send a buffer status report to the donor node to send to the relay node when the buffered data value exceeds the threshold. The buffered data value represents either data in the UE buffer or data in the relay buffer.

  According to an embodiment of another aspect of the present invention, a method in a communication system is provided, wherein the communication system includes a donor node downlink via a relay node to a defined one of a plurality of user equipments. The relay node stores the data received from the donor node in the downlink buffer before transmission to the defined user equipment. The method reports a downlink buffer status from the relay node to the donor node when the downlink buffered data value representing the data stored in the downlink buffer exceeds a threshold at the relay node. Including sending.

  Advantageously, sending a downlink buffer status report when a threshold is exceeded introduces a level of control into the signaling process involved in sending the report, thereby enabling periodic downlink The need to send a buffer status report is alleviated. For example, the threshold is set to be sent only when the downlink buffer is close to being overloaded, in which case it is desirable for the donor node to reduce the rate at which data is sent to the relay node.

  The downlink buffered data value represents the amount of data in the downlink buffer. Accordingly, the threshold is either the maximum or minimum amount of data that triggers a downlink buffer status report to be sent to the donor node when the amount of data in the downlink buffer is above or below. Represent. There may be more than one threshold, any of which is exceeded to trigger a downlink buffer status report.

  Alternatively, the downlink buffered data value represents the rate of change in the downlink buffer. Accordingly, the threshold may represent the maximum rate of change, either positive or negative, of the amount of data in the downlink buffer with respect to time. If the amount of data in the downlink buffer increases rapidly, it is desirable to send downlink buffer status information to the donor node.

  The downlink buffer status report may include information representing the amount of data in the downlink buffer, or may include an indication as to why the report was sent. For example, the suggestion is the percentage of downlink buffer filling above the upper threshold.

  The combination between these thresholds and the downlink buffered data values so that there are a number of thresholds that can be exceeded to trigger the downlink buffer status report to be sent to the donor node May be used.

  Preferably, an embodiment of this aspect of the invention is that the donor node receives a downlink buffer status report, and based on the received downlink buffer status report, relay node to donor node Adjust the donor-relay transmission characteristics that define the transmission of data to.

  For example, the downlink buffer may be overloaded by receiving data from the donor node at a faster rate than the data being transmitted to each defined user equipment. In order to avoid buffer overflow, it is desirable for donor nodes to reduce the rate at which data is transmitted to relay nodes by adjusting transmission characteristics or reducing the bandwidth allocated for such transmissions.

  Preferably, in an embodiment of this aspect of the invention, the data transmitted from the donor node to the relay node includes a set of donor-UE transmission characteristics, including user equipment suggestions and quality of service requirements as the data destination. And each data stream is assigned a QoS label from the set of QoS labels according to the quality of service requirements included in the donor-UE transmission characteristics that define the data stream. .

  QoS labels are a way to group data streams that have similar sets of transmission characteristics. This can simplify the labeling which increases the efficiency of signal transmission. By labeling the data streams in this way, the relay node and the donor node can individually handle the data streams having different transmission characteristics.

  The QoS label is, for example, the QCI label of Table 1, and indicates the quality of service requirements according to Table 1.

  A data stream may be established at the donor node.

  Data streams are transmitted over the interface by bearers and are distinguished from each other by their endpoints, or are distinguished from each other by some other characteristic that defines the data stream, such as quality of service requirements. Bearers carrying a data stream are distinguished from each other by their own transmission characteristics or from each other by the transmission characteristics of the data stream. The data in the data stream is a series of consecutive marked packets. A data packet transmitted in a stream contains several labels or suggestions of characteristics that define the stream. Once established, the data stream remains established until the end of the associated data transmission session, eg, the end of a VoIP call, the end of file transfer over FTP.

  Data streams with the same QoS label are sent over the single radio bearer from the donor node to the relay node (over the Un interface).

  Advantageously, embodiments of this aspect provide the threshold at the donor node based on the QoS label of the data stream currently established for use as a threshold at the relay node, and the threshold at the relay node. Further comprising transmitting.

  The donor node is responsible for establishing the data streams and has information representing the number of currently established data streams with respective QoS labels. The threshold is calculated based on this information. For example, if there are multiple data streams with QoS labels indicating a guaranteed bit rate, the donor node may refrain from reducing the rate at which data is sent to the relay node, so the downlink buffer The amount of data serving as a threshold value in the relay buffer is set to be relatively large before the status report needs to be sent.

  The donor node calculates one or more thresholds whenever there is a change in the number of data streams currently established according to the algorithm. Alternatively, the donor node is pre-loaded with a look-up table having a threshold value corresponding to each combination of the number of data streams having a predetermined QoS label.

  In an embodiment of this aspect of the invention, the relay node has a downlink buffer for each different QoS label of the currently established data stream, or alternatively, each relay node has its currently established data. Has a downlink buffer for the stream.

  A preferred method of implementing this aspect further includes providing a threshold based on a currently established data strip QoS label for each buffer of the relay node, and transmitting the threshold to the relay node. In this case, when the downlink buffered data value specific to the QoS label exceeds the threshold provided for the relay buffer with the same QoS label, the downlink buffer status report is sent from the relay node to the donor node. The downlink buffered data value transmitted and specific to the QoS label represents the data stored in the downlink buffer having the particular QoS label.

  The downlink buffered data value specific to the QoS label represents the amount of data in the associated downlink buffer or represents, for example, the rate of change in the amount of data in the buffer. As with buffered data values specific to QoS labels, buffered data values and downlink buffered data values, the choice as to what the value represents depends on the threshold being compared. . One skilled in the art will appreciate that the implementation choices applicable to certain types of buffered data values and associated thresholds are many applicable.

  Since the data streams are grouped into radio bearers based on the QoS labels of the transmissions, the donor node can individually adjust the transmission characteristics of each radio bearer. Thus, by receiving a report from the relay node when the buffer of the data stream with a particular QoS label is overflowing or not fully utilized, the donor node is dedicated to the associated radio bearer. Radio resources can be adjusted.

  According to an embodiment of another aspect of the invention, there is provided a communication system having a plurality of user equipments, a relay node having a downlink buffer, and a donor node. In this system, the donor node transmits data to one of the plurality of user equipments on the downlink, and the relay node donors to the downlink buffer before transmission to one of the plurality of user equipments. When the downlink buffered data value that stores the data received from the node and represents the data stored in the downlink buffer exceeds a threshold, the relay node reports the downlink buffer status to the donor node. Is sent out.

  According to an embodiment of another aspect of the invention, a relay node is provided for use in a communication system that also includes a plurality of user equipment and a donor node, the relay node having a downlink buffer, and a plurality of Receive data from the donor node for one of the user equipment, store the data in the downlink buffer and transmit the data stored in the downlink buffer before transmission to one of the plurality of user equipments A downlink buffer status report is sent to the donor node when the representing downlink buffered data value exceeds a threshold.

  In accordance with another aspect of the present invention, a donor node for use in a communication system that also has a relay node that stores data in a downlink buffer prior to transmission to the plurality of user devices and one of the plurality of user devices. And the donor node transmits data downlink to one of the plurality of user equipments via the relay node, and the donor node is downlink buffered representing data in the relay buffer to the downlink. When the data value is exceeded, it provides a threshold to trigger the relay node to send a report of the downlink buffer status to the donor node and sends it to the relay node.

  Those skilled in the art will appreciate that the features of the embodiments of the invention described or claimed can be easily combined with the features of other embodiments. In particular, the described communication system, relay node, donor node or other device has means or functions for performing the described method.

  Preferred features of the invention will now be described by way of example with reference to the accompanying drawings.

It is a figure which shows the relationship between the protocol layers for LTE. It is a figure which shows the simple network architecture for LTE. 1 is a diagram illustrating an LTE-A network architecture including relay nodes. FIG. It is a figure which shows use of the bearer in the conventional LTE / SAE (System Architecture Evolution) system. It is a figure which shows the exchange of the message in establishment of the bearer in a LTE / SAE system. FIG. 3 is a conceptual representation of a report according to a method for implementing the present invention. It is a flowchart expressing embodiment of this invention. 2 is a conceptual representation of a radio bearer in an embodiment of the present invention. It is a flowchart expressing embodiment of this invention. It is a figure which shows the conceptual expression of the report in this invention.

  In FIG. 6, a communication system having two user equipments 211 and 212, a relay 240 (relay node), a DeNB 220 (donor node) and a serving gateway 230 is shown. The first user equipment 211 is established by the UE buffer 2111 of the data stream established by the set of transmission characteristics given the QoS label '1', and by the set of transmission characteristics given the QoS label '2'. A UE buffer 2112 for the data stream. In response to this, the second user equipment 212 receives the UE buffer 2121 of the data stream established by the set of transmission characteristics given the QoS label '1', and the set of transmission characteristics given the QoS label '2'. UE buffer 2122 of the data stream established by A block in the buffer represents data stored in the buffer.

  The relay node 240 has a relay buffer 2401 for data in the data stream established by the transmission characteristic given the QoS label '1', and the data established by the transmission characteristic given the QoS label '2'. It has a relay buffer 2402 for data in the stream. Further, the block in the buffer represents the data stored in the buffer.

  In this example, data streams are generated at user equipment 211, 212 and their transmission characteristics specify donor node 220 as their destination. However, the data stream may be multiplexed into a larger stream, eg, for transmission of data from the relay node 240 to the donor node 220. The data stream includes information indicating the user equipment from which the data stream was generated, and at the donor node 220, the individual data streams are identified in the received multiplexed data stream. The same is true for embodiments in which the data stream is transmitted via a radio bearer.

  In FIG. 6, the Un radio interface is crossed by bearers marked with Un. This Un bearer includes several data streams combined, multiplexed or otherwise included. However, it is preferred that a separate radio bearer exists for each QoS label so that the radio resources allocated for the transmission of data streams with different QoS labels are adjusted independently of each other.

  The Uu interface is marked Uu1 and Uu2, and the Uu interface is considered for each user device. Since the data streams at the first user equipment 211 have different QoS labels and thus different QoS requirements, a separate Uu radio bearer is used for each data stream in transmitting data to the relay node 240. The transmission characteristics of the radio bearer reflect the transmission characteristics of the data stream, but the start point and the end point may be different. The same applies to the data stream from the second user device 212. Individual data streams are not represented in FIG. 6 except for UE buffers 2111, 2112, 2121, 2122 and relay buffers 2401, 4022.

  At the relay node, the data stream from each of the user equipments 211 and 212 is stored in a buffer according to the QoS label. However, the data from each user device is different from each other because the data stream includes an indication of the user device from which the data stream was generated. The data is then sent to the donor node via the Un interface via the Un radio bearer for each QoS label. The transmission characteristics used for the Un radio bearer depend on the QoS label of the currently established data stream.

  The arrow in FIG. 6, which is the height of the BSR, represents the contribution from the respective buffer to the entire buffered data value / transmission value, and the value increases as the height increases.

  The UE buffer status report is sent from either the user equipment 211 or 212 to report the amount of data in each buffer of the user equipment to the relay node 240. The relay node then combines these UE buffer status reports with values indicating the amount of data in each of the relay buffers 2401, 4022 to generate buffered data values for comparison with thresholds. To do. Once the threshold is exceeded, the relay node sends a relay buffer status report to the donor node 220.

  FIG. 7 is a flowchart representing a method of practicing the present invention. In step S1, a data stream is established at a relay node 240 for a specific user equipment 211, 212 and service. A data stream is established by defining a set of transmission characteristics, and this set of transmission characteristics indicates the donor node 220 as an endpoint of the data stream.

  In step S2, for each of the established data streams, the QoS label (which is the same as the QoS classification identifier (QCI) information) is sent from the relay node 240 to the donor node 220 to which the relay node is connected via the Un interface. Sent. Thus, the information required at the relay to communicate with the user equipment 211, 212 connected to the example 240 is available to the donor node 220 in several ways (possibly reduced size). is there. For example, the relay node 240 may be aware of the complete set of transmission characteristics for each currently established data stream that is proceeding through the relay node 240, and the donor node 220 may recognize those data streams. Only the QoS label may be recognized.

  In step S3, a set of reporting thresholds for the amount of data buffered for different QoS labels is sent from the donor node 220 to the relay node 240 so that the donor node 220 defines a threshold for reporting the relay buffer threshold. Is done. The threshold is calculated according to some predetermined algorithm, or the donor node stores a lookup table, where the combination of the number of data streams per QoS label is a specific threshold Linked to a set. The set of thresholds includes one or more thresholds for each of the different QoS labels of the currently established data stream. Alternatively, regardless of whether the currently established data stream in the communication system has that QoS label, the threshold set includes one or more thresholds for each possible QoS label.

  Step S3 can also be performed at another point in the process, and may not be in constant terms with respect to other steps. For example, the threshold may be set periodically based on current information held at the donor node. Alternatively, the threshold may be set only once when the relay is installed in the network. A threshold linked to a particular QoS label may be provided whenever there is a change in the number of data streams with that QoS label. Alternatively, the threshold may be based on the percentage of data streams having a particular QoS label for the total number of data streams, rather than the number of data streams themselves.

  The relay node 240 combines the data amount in the UE 2111, 2112, 2121, 2122 and the data amount in the relay buffer 2401, 4022, and generates a combined value. In this example, the relay node 240 generates a combined value for each of the different QoS labels based on the amount of data in the buffer of the data stream having the QoS label in question. In step S4, the combined value is compared with an associated threshold from a set of thresholds (according to the QoS label).

  In step S5, if one of the thresholds is exceeded, a relay buffer status report is sent from the relay node 240 to the donor node 220. The relay buffer status report includes at least an indication of the identity and magnitude of the combined value above its threshold. The relay buffer status report may contain more than one combined value detail.

  In step S6, the received report is used by donor node 220 to adjust the amount of radio resources allocated to Un radio bearers carrying data streams with QoS labels that exceed a threshold.

  FIG. 8 illustrates adjustments in radio resources allocated to Un radio bearers, which is a set of transmission characteristics that define the transmission of data from relay node 240 to donor node 220.

  In the first configuration in FIG. 8, the user apparatuses 211 and 212 have Uu radio bearers on the left of the arrows, and transmit data to the relay node 240 via the Uu radio bearers. For clarity in this example, consider the case where each Uu radio bearer is transmitting data in only a single data stream, where in each case the single data stream has the same QoS label. Thus, all data arriving at the relay node 240 has the same QoS label and there is only a single Un radio bearer. For example, each of the user devices 211 and 212 may be included in a voice call. At relay node 240, data from these data streams is buffered in a single buffer. This is because the relay node 240 has a relay buffer for each QoS label and both data streams have the same QoS label. Data from the relay buffer is transmitted to the donor node 220 over the Un radio interface via the Un radio bearer. An Un radio bearer is a defined set of transmission characteristics dedicated to carrying a data stream with a particular QoS label and has a small bandwidth in the first configuration.

  In the second configuration, to the right of the arrow, the first user equipment 213 joins the communication system and establishes a data stream that transmits voice data to the donor node 220. Data is first transmitted to the relay node via the Uu radio bearer. Since the user device 213 is transmitting audio data in this example, the data stream of the audio data from the user device 213 is given the same QoS label as the data streams from the user devices 211 and 213, and therefore It is sent to the donor node 220 by the same Un radio bearer.

  Returning to step S <b> 2 of FIG. 7, the donor node 220 is notified of the QoS label of the data stream established for the user device 213. Donor node 220 reduces the threshold for that QoS label in response to an increase in the number of user equipments with established data streams having the same QoS label. Between the first configuration and the second configuration, due to the reduction in threshold, the threshold is exceeded and a relay buffer status report is sent from relay node 240 to donor node 220 (from FIG. 7). Steps S4 and S5). Then, as in step S6 of FIG. 7, the donor node 220 increases the bandwidth dedicated to the Un radio bearer and becomes a problematic QoS in the second configuration compared to the first configuration. This leads to an increase in the size of the label Un radio bearer.

  FIG. 9 is a flowchart representing a method for practicing the present invention. The steps in FIG. 9 are performed at relay node 240. In step S11, the buffer state value is compared with a threshold value. As explained earlier, buffer state values and thresholds take a number of forms. In this example, the buffer status value represents the total amount of buffered data in the UE buffer and relay buffer of the data stream having a particular QoS label. The threshold is set by the donor node 220, for example, an upper bound on the amount of data from the data stream having that QoS label stored in the buffer before the relay buffer status report is sent to the donor node 220. is there.

  In step S12, the result of the comparison (whether the threshold is exceeded or not exceeded) is confirmed. If the result is negative, that is, if the threshold is not exceeded, the flow returns to step S11, and the threshold is continuously monitored. If the threshold is exceeded, the flow proceeds to step S13 where a relay buffer status report is sent to the donor node 220. The relay buffer status report includes an indication of the amount of data in the buffer of the data stream having the particular QoS label that triggered the outgoing report.

  FIG. 10 is a conceptual diagram illustrating several reports relating to a method of implementing the present invention. Since the scenario shown in FIG. 10 is generally the same as the scenario in FIG. 6, only the differences between the two figures are described in detail here.

  Relay node 240 includes downlink buffers 2403 and 2404 that store data prior to transmission to user equipment.

  Arrows marked with DL Un indicate the method of data transmitted from the donor node 220 to the relay node 240 over the Un interface. Data transmitted from the donor node 220 to the user equipment is transmitted in a data stream having defined transmission characteristics such as start and end points and quality of service requirements. The quality of service requirements are indicated by a QoS label that is the same as the QCI label in Table 1, or may follow some other system that summarizes the QoS requirements. Data streams having the same QoS label are grouped and transmitted from donor node 220 to relay node 240 with radio bearers having transmission characteristics corresponding to the carrying data stream. For example, voice data destined for user equipment 211 and voice data destined for user equipment 212 are transmitted in separate data streams, but assuming relay nodes 240 (assuming that the data streams have the same QoS label in each case). Is transmitted from the donor node 220 by a single Un radio bearer.

  At relay node 240, there is a separate downlink buffer for each data stream so that voice data destined for user equipment 211 is stored in a separate buffer from voice data destined for user equipment 212. If the user equipment 211 is downloading a file, for example via FTP, this is in a data stream with a different QoS label, and thus a separate downlink at the relay node 240 before transmission to the user equipment 211. Has a buffer.

  The downlink indicates the direction of data transmission in the network architecture, that is, the direction toward the user equipment.

  The threshold is signaled in advance by donor node 220 for each QoS label downlink buffer and sent to relay node 240 where it is compared with the data in downlink buffers 2403 and 2404. For example, when the threshold is the upper limit threshold of the amount of data that can be stored in the downlink buffer of the data stream with a predetermined QoS label, the data amount in the downlink buffers 2403 and 2404 of the data stream with the QoS label is Compared with If the threshold is exceeded, a downlink buffer status report is sent from the relay node 240 to the donor node 220 indicating the amount of data in the downlink buffer in question.

  As explained above, the threshold is a lower threshold or is related to the rate of change of the data level in the buffer.

  A threshold may be sent for each buffer such that a buffer that meets a certain threshold triggers a downlink buffer status report. Alternatively, the buffer is set for a combination of downlink buffers used for data streams having a particular QoS level. The radio resource dedicated to the radio bearer is then adjusted, carrying data in the data stream with that QoS label, from the donor node to the relay node. For example, there is a risk of buffer overrun if the amount of data in one or all of the buffers used for the data stream having QoS label '1' is too large. A threshold (set by the donor node) is exceeded, a downlink buffer status report is sent to the donor node, and bandwidth is allocated to the associated Un radio bearer that is reduced to slow down the rate of arrival.

  Although different aspects of the invention have been given individually, it should be understood that the features of the different aspects can be combined. For example, the threshold described for data in the relay buffer is applicable to the downlink buffer. Further, although the features have been described as a method, it should be understood that an apparatus having means and functions for performing the method is implicitly disclosed.

  In any of the foregoing aspects, the various features may be implemented in hardware or as software modules that execute on one or more processors. Features of one aspect may apply to any of the other aspects.

  The present invention also provides a computer program or computer program product for performing any of the methods described herein, and a computer-readable recording medium storing a program for performing any of the described methods. To do.

  The computer program embodying the present invention may be stored in a computer readable recording medium, in the form of a signal such as a downloadable signal provided from an Internet website, or any of a number of formats. It may be.

Claims (20)

A method in a communication system in which a plurality of user equipments transmit data to a donor node in an uplink via a relay node,
The plurality of user equipments each store the data in its own UE buffer before transmission to the relay node, and the relay node stores the plurality of data in a relay buffer before transmission to the donor node. Store data received from other user devices,
The method is
A relay node sending a report of the status of the relay buffer from the relay node to the donor node when the buffered data value exceeds a threshold, the buffered data value comprising: Represents data stored in the UE buffer, or data stored in the relay buffer,
A method characterized by that. The buffered data value represents a combination of data stored in the UE buffer and data stored in the relay buffer;
The method of claim 1. The donor node receives the relay buffer status report and, based on the received relay buffer status report, defines a relay-donor transmission characteristic that defines transmission of data from the relay node to the donor node. Further comprising the step of adjusting,
The method according to claim 1 or 2. Data transmitted from each of the plurality of user equipments to the relay node is transmitted in a data stream established with a set of UE transmission characteristics of the data stream, including quality of service requirements,
The method is
Steps defining the set of UE transmission characteristics for each new data stream;
Transmitting information representing a set of defined UE transmission characteristics from the relay node to the donor node;
The method according to any one of claims 1 to 3, further comprising: The relay node selecting, for each set of UE transmission characteristics, a QoS label according to a quality of service requirement of the new data stream from a set of QoS labels;
Transmitting the QoS label as information representing the defined set of UE transmission characteristics from the relay node to the donor node;
The method of claim 4 further comprising: Providing a threshold based on a QoS label of a currently established data stream for use by the donor node as a threshold at the relay node;
Transmitting the threshold to the relay node;
The method of claim 5 further comprising: Each user equipment has a UE buffer dedicated to each data stream from each user equipment to the relay node,
The relay node has a buffer for each different QoS label of the currently established data stream;
The method of claim 5. Further comprising, for each buffer of the relay node, the donor node providing a threshold based on a QoS label of a currently established data stream and transmitting the threshold to the relay node;
The buffer status report is sent from the relay node to the donor node when the buffered data value specific to the QoS label exceeds a threshold provided for the relay buffer having the same QoS label, and the QoS Specific buffered data values are data stored in the UE data buffer dedicated to a data stream having a specific QoS label, data stored in the relay buffer having the same QoS label, or Represents a combination of these two data,
The method of claim 7. A plurality of user devices each having a UE buffer;
A relay node having a relay buffer;
A communication system having a donor node,
Each of the plurality of user equipments transmits data to the donor node via the relay node to the uplink, and stores the data in its own UE buffer before transmission to the relay node;
The relay node stores data received from the plurality of user equipments in the relay buffer prior to transmission to the donor node, and reports buffer status when the buffered data value exceeds a threshold To the donor node and the buffered data value represents data in the UE buffer or data in the relay buffer;
A communication system characterized by the above. A relay node used in a communication system,
The communication system includes a plurality of user devices each having a UE buffer for storing data and a donor node before transmitting to the relay node in the uplink,
The relay node has a relay buffer, receives data from each of the plurality of user devices for transmission to the donor node, and stores the relay buffer in the relay buffer before transmission to the donor node. Store data and send a buffer status report to the donor node when the buffered data value exceeds a threshold, and the buffered data value is either the data in the UE buffer or the relay buffer Representing any of the data,
A relay node characterized by that. A donor node used in a communication system,
The communication system has a plurality of user equipments each having a UE buffer for storing data before transmitting to a relay node in the uplink, and a relay buffer for storing the data before transmission to the donor node A relay node,
The donor node provides a threshold to trigger the relay node to send a buffer status report to the donor node when exceeded by a buffered data value and sends the relay node to the relay node; The buffered data value represents either data in the UE buffer, data in the relay buffer, or a combination of these two data.
A donor node characterized by that. A method in a communication system, comprising:
In the communication system, a donor node transmits data to a defined user device among a plurality of user devices in a downlink via a relay node, and the relay node transmits to the defined user device. Before the data received from the donor node in a downlink buffer,
The method is
The relay node sends a downlink buffer status report from the relay node to the donor node when a downlink buffered data value representing data stored in the downlink buffer exceeds a threshold value Including steps,
A method characterized by that. The donor node receiving a report of the downlink buffer status and a donor defining a transmission of data from the donor node to the relay node based on the received downlink buffer status report; Adjusting the relay transmission characteristics;
The method of claim 12 further comprising: Data transmitted from the donor node to the relay node is transmitted in an established data stream having a set of donor-UE transmission characteristics including user equipment indications as a destination of the data and quality of service requirements. ,
Each data stream is assigned a QoS label from a set of QoS labels according to quality of service requirements included in the donor-UE transmission characteristics that define the respective data stream.
14. A method according to claim 12 or 13. Providing a threshold based on a QoS label of a currently established data stream for the donor node to use as a threshold at the relay node;
Transmitting the threshold to the relay node;
15. The method of claim 14, further comprising: The relay node has downlink buffers with different QoS labels of the currently established data stream;
The relay nodes each have a downlink buffer of a currently established data stream;
16. A method according to claim 14 or 15. Providing, for each buffer of the relay node, a threshold based on a QoS label of a currently established data stream at the donor node, and transmitting the threshold to the relay node;
The downlink buffer status report indicates when the downlink buffered data value specific to the QoS label exceeds a threshold provided for the relay buffer having the same QoS label, from the relay node to the donor. A downlink buffered data value sent to a node and specific to the QoS label represents data stored in the downlink buffer having a specific QoS label;
The method of claim 16. A plurality of user devices;
A relay node having a downlink buffer;
A communication system comprising a donor node,
The donor node transmits data to one of the plurality of user equipments in a downlink;
The relay node stores data received from the donor node in a downlink buffer before transmission to the one of the plurality of user equipments, and stores the data stored in the downlink buffer. Sending a downlink buffer status report to the donor node when the downlink buffered data value representing exceeds a threshold;
A communication system characterized by the above. A relay node in a communication system,
The communication system includes a plurality of user devices and a donor device,
The relay node has a downlink buffer, receives data from the donor node for one of the plurality of user devices, and transmits to the one of the plurality of user devices. Prior to storing the data in the downlink buffer and reporting a downlink buffer status when a downlink buffered data value representing the data stored in the downlink buffer exceeds a threshold. Send to donor node,
A relay node characterized by that. A donor node used in a communication system,
The communication system includes a plurality of user equipments and a relay node that stores data in a downlink buffer prior to transmission to one of the plurality of user equipments;
A donor node transmits data via the relay node to one of the plurality of user equipments in the downlink;
Providing a threshold for triggering the relay node to send a direction of a downlink buffer state to the donor node when exceeded by a downlink buffered data value representing data in the downlink buffer; Send to the relay node;
A donor node characterized by that.

Images